The present invention relates to the treatment of an intracorporeal lumen, by applying or fitting an intraluminal prosthesis, or endoprosthesis, in said corporeal lumen, for example in an artery or a vein, in the field of angiology. More particularly, the invention relates to a surgical treatment assembly which facilitates the positioning of a vascular endoprosthesis in a blood vessel.
According to the methods commonly used in vascular surgery, the fitting of vascular endoprostheses or the like requires the use of an application device. For example, the techniques for introducing and applying endoprostheses, either expandable using a balloon or autoexpansible, are generally well known.
In the case of an expandable endoprosthesis, it is generally presented in its retracted configuration, on and around an inflatable balloon, introduced intravenously or intra-arterially with the balloon, and thus brought to the site of the lesion or obstruction to be treated. In this position, the balloon is then inflated in order to bring the endoprosthesis into its deployed configuration, and thus treat the lesion or obstruction. The problems often encountered with a system of this type are due to the endoprosthesis being held poorly on the balloon, in particular resulting in the endoprosthesis being detached from the balloon, or premature release of the endoprosthesis which may result in it being positioned incorrectly, as well as the possibility of the balloon being punctured by one of the ends of the prosthesis, which is often made of metal.
In the case of an autoexpansible endoprosthesis, generally consisting of a shape-memory material, it is often introduced into the vein or artery in two concentric tubes which overlap, and therefore in its retracted configuration, and withdrawal of the tube releases the endoprosthesis with the result that it expands into the deployed configuration.
In order to prevent any displacement of an expandable endoprosthesis along its intra-arterial or intravenous route to the site where it is installed, it is known to use folds of flexible plastic, arranged at the front and rear of the balloon, with the circular edges of the intraluminal prosthesis having previously been slid under these folds, so that it is held by them and cannot be displaced forward or backward. When the balloon is inflated, its radial expansion, and consequently the radial expansion of the endoprosthesis, causes the latter to shorten longitudinally and allows it to detach from the balloon. However, this solution does not make it possible to control the application of all types of intraluminal prostheses, and in particular cannot be applied to autoexpansible endoprostheses.
Another solution has been provided by document WO-A-95/07667, which describes a detachable and hardenable balloon combining the act of angioplasty and the fitting of an internal sheath, which then acts as a stent. The chemical hardening is brought about by applying heat or light, once the balloon has been put in place and inflated, and it is released by the chemical degradation of separation zones consisting of polymers different than those constituting the rest of the balloon. However, this solution does not permit straightforward control of the positioning of the stent balloon, because the chemical degradation and hardening conditions which need to be applied may lead to uncontrolled release of degradation products which are potentially toxic at the local or systemic level.
There has therefore been the need to find an assembly for treating an intracorporeal lumen which includes all the components needed for this treatment in a compact form, these being "packaged" in some way so that they can be deployed with precision and without risk to the patient, in a straightforward and controllable fashion.